Engineering plastics such as aromatic polyether ketone resin are thermoplastic resins having high heat resistance, high mechanical strength, and high dimension stability, and thus are used in various applications.
Fluororesin has excellent properties such as slidability, heat resistance, chemical resistance, solvent resistance, weather resistance, flexibility, and electric properties, and is used in a wide variety of fields such as the automobile field, the industrial machinery field, the OA equipment field, and the electric and electronic equipment field. However, fluororesin is inferior to crystalline heat-resistant thermoplastic resin in mechanical properties and physical heat resistance represented by, for example, a heat deflection temperature in many cases. Further, fluororesin is also inferior to amorphous heat-resistant thermoplastic resin in dimension stability. Thus, the field where fluororesin can be used is limited, as a matter of fact.
Under such circumstances, techniques of using thermoplastic resin and fluororesin in combination are studied. For example, Patent Literature 1 discloses a resin composition including an aromatic polyether ketone resin (I) and a fluororesin (II) capable of providing a molded article having both a low coefficient of kinetic friction and a high limiting PV value, wherein the fluororesin (II) is a copolymer of tetrafluoroethylene and a specific perfluoroethylenic unsaturated compound, the aromatic polyether ketone resin (I) and the fluororesin (II) satisfy a mass ratio (I)/(II) of 95:5 to 50:50 and a melt viscosity ratio (I)/(II) of 0.3 to 5.0, the fluororesin (II) is dispersed as particles in the aromatic polyether ketone resin (I), and the fluororesin (II) has an average dispersed particle size of smaller than 3.0 μm.
Patent Literature 2 discloses an insulated wire including a conductor (A) and an insulation layer (B) formed around the conductor (A), wherein the insulation layer (B) is formed from a resin composition containing an aromatic polyether ketone resin (I) and a fluororesin (II), the fluororesin (II) is a copolymer of tetrafluoroethylene and a specific perfluoroethylenic unsaturated compound, and the aromatic polyether ketone resin (I) and the fluororesin (II) satisfy a melt viscosity ratio (I)/(II) of 0.3 to 5.0.